Refrigeration system with heat reclaiming means



June 30, 1959 L. K. QUICK 2,892,324

REFRIGERATION SYSTEM WITH HEAT RECLAIMING MEANS Filed May 51, 1955 AIRFILTER 9 COIVDEI SER COMPQFSSOR EEFB/G EQ/IrE SPA c E 6 1575? K. QUICKa, INVENTOR.

United States Patent REFRIGERATION SYSTEM WITH HEAT RECLAIMIN G MEANSLester K. Quick, Eugene, Oreg.

Application May 31, 1955, Serial No. 512,112

Claims. (Cl. 62-455) This invention relates to a refrigeration systemand more particularly to a refrigeration system wherein provision ismade for maintaining the system operating within an optimum range sothat greater efficiency of operation may be had.

In the operation of the ordinary refrigeration system it is wellrecognized that using the ordinary refrigerating gases the operatingefliciency of the system is dependent upon operation within a relativelynarrow range pressure of the refrigerant gas in the compressor. Pressureof a gas is directly related to temperature.

It is therefore an object of this invention to provide a refrigerationsystem in which means are provided for maintaining the operation of thesystem within an optimumrange of compressor head pressures of therefrigerant gas employed.

' operating within a definite temperature range so that the headpressure at the compressor is maintained within the said optimum range.

Another object of this invention is to utilize heat generated in therefrigeration system for maintaining air temperature such that the saidair when passing over the condensing unit of the refrigerating system isat a temperature which will maintain the refrigerant pressure in thesystem and at the compressor within the optimum range.

' Another object of this invention is to provide a unique and novel aircooled condensing unit for use in a refrigeration system wherein thepressure of the refrigerant gas is maintained within the optirmnn range.

Other objects and advantages of this invention it is believed will beapparent from the following detailed description of a preferredembodiment thereof as illustrated in the accompanying drawings.

In the drawings:

Figure 1 is a diagrammatic view of a refrigeration system embodying myinvention illustrated as incorporated within a building.

Figure 2 is a diagrammatic view of a modified form of condensing unitapplicable for use in the system embodying my invention.

The refrigeration system embodying my invention includes the ordinarygas refrigerating cycle wherein the the commonly employed refrigeratinggases is compressed in a compressor 1 to a pressure such that when thegas is passed through a condenser 2, the gas will be condensed "to aliquid. The condensed refrigerant passes from the condenser to areceiver 3 and from the receiver passes through the expansion valve 4 tothe evaporator 5 wherein may be used for any of the common purposes forwhich gaseous refrigerant such as ammonia, Freon, or other of .2-B and2-C, which may be connected, if desired, to

other evaporators located in an ice cream case and freezer case, forexample. The condenser in this case is an aircooled condenser which maybe of either the form illustrated in Figures 1 or 2 hereof.

As illustrated in Figure 1, the condenser is positioned within a casing6 which in this case is illustrated as in an elevated position within anenclosure, room or store and the casing is provided with a room inlet 7taking air from within the store or building and an outside air inlet 8through which air may pass from the outside of the building. Within thecasing 6 there is provided a fan 9 operated by a motor 10 which drawsthe air over the condenser 2 and may discharge the said air either intothe building or store through an outlet 11 or into the outsideatmosphere through an outlet 12.

The air circulation system as provided is such that when the air isdrawn from the building through the inlet 7 it is preferably dischargedback into the building through the outlet 11 and in passing over thecondenser 2 absorbs the heat from the gas being condensed and operatesas an aid to the heat of the building.

Positioned within the casing 6 is an auxiliary heating element 13 whichmay be either a hot water, steam or other heating unit which willsupplement the heating of the air to that degree required to maintainthe temperature within the store or building at the desired temperatureof say 65 F. during winter or the colder days of the year. In the hotterdays when heat is not required within the store or building, the dampers14 and 15 controlling the air passage through the inlet 7 and outlet 11are closed and the dampers 16 and 17 controlling the air passage for theoutside air through the inlet 8 and out the outlet 12 are opened so thatoutside air is drawn over the condensing unit 2 to condense therefrigerating gases therein and this heated air which is not thendesired within the store or building is discharged into the atmosphere.

Under ordinary conditions of operation, the range of temperature atwhich the condensing unit 2 would be operating in the system as thusoutlined is between 65 F. and the temperature of the outside or ambienttemperature which may under ordinary circumstances range between amaximum of to F., or the entire temperature range would be a range of 35F.

Thus with the system as indicated in Figure 1, the head pressure of therefrigerant gas at the compressor would not drop too far below theoptimum pressure of approximately lbs. for a Freon gas and even in theworst conditions of summer, would not build up to a temperature suchthat the operating efliciency would be seriously impaired.

In order that the system may operate without care, I have provided acontrol motor 18 which is connected through a lever system 19 with thedampers 14, 15, 16 and 17 and with a temperature switch control 20 suchthat when the temperature within the building is such that no heating ofthe return air is required, that the motor 18 will be energized tooperate to close the dampers 14 and 15 and open the dampers 16 and 17thus utiliz ing the ambient outside air over the condenser forcondensing the refrigerant gases.

In Figure 2 I have illustrated a modified form of condensing elementwhich has the advantage over that illustrated in Figure 1 of maintainingthe condenser operating at an air temperature which is within muchnarrower limits than in the example set forth in Figure 1.

In this modified form of my invention I employ, as in the illustrationof Figure 1, a finned type air operating condensing coil 2a which in allrespects may be precisely the same in construction and operation as thecondenser. 2. In the air stream maintained within the casing 6a and inadvance of the condenser 2a I removably position a fibre pad 21a whichis a wettable pad similar in all respects to those used in evaporativecooling units for evaporating water in an air stream to lower thetemperature of the air passing through the pad.

In this modification of my invention when outside elevated temperatureair is being used to cool the refrigerant gases within the condenser 2a,water is passed over the pad 21a so that the said air is cooled by theevaporation of the water in passing through the pad. In this case thesensing element of a thermostat 22a is located in the air inlet 8ahaving the damper 16a therein. The thermostat may be set to operate, forexample, at 80 F. air to operate the solenoid valve 23a which controlsthe water drain from the pan 24a and to operate a second solenoid valve25a in a water supply line 26a.

Positioned within the water supply line is a pressure operated switch27a which is positioned within the circuit controlling the currentsupply to the electric motor 28a operating the water pump 29a. A floatvalve 30a may be provided within the water pan 24a to control the waterlevel within the said pan.

The operation of this system is that when the outside air rises to atemperature of 80 F., or above, the normally opened drain valve 23awhich is positioned within the drain 31a of the pan 24a is closed andthe solenoid valve 25a at the water supply line 26a is opened to permitwater under pressure to flow through the line 26a and to pressurize thewater pressure switch 27a setting in operation the motor 28a driving thewater pump 29a. Thus water is supplied through the spray elements 32aonto the pad 21a. Air from the outside is then drawn over the pad 21a bymeans of the fan 9a. The air in passing over the pad is cooled toapproximately to F., depending upon the wet bulb temperature of theoutside air. This maintains the air passing over the condenser 2a withinthe very narrow limits of the desired temperature within the store whichmay be from 65 F. in winter to, say a maximum of or F. in the summer,and thus maintains the head pressure of the refrigerant gas within thevery narrow optimum limits desired and as desired for the particularrefrigeration system utilized and the refrigerant gas being employedwhich, for a Freon gas, is within the range of lbs. per square inch atthe compressor.

In the systems employing my invention, whether they be that of Figures 1or 2, the auxiliary heater 13 may be set into operation by means of anysuitable thermostatic control well understood in this art when the heatsupplied by passing the air over the condenser 2 is insufficient toraise the building temperature to the desired point.

In the system illustrated in Figure 2, the solenoid operated valve 25ais of the three-way or self-draining type, that is, it is provided witha drain outlet 33a which is opened to drain the supply line leading fromthe valve 25a to the pan 24a when the solenoid valve is closed. When thetemperature of the outside air falls below that temperature betweenwhich the thermostat 22a is set, the vmve 23a is also opened drainingthe pan 24a. Thus when air is circulated over the condenser Zn fromWithin the building, water is not supplied to the pad 21a and noevaporative cooling of this air is attained. By utilizing the automaticdraining principles as herein set forth,

I have provided for the automatic day and night or winter control of thesystem illustrated in Figure 2 because the system is made self-draining.As no water is employed in this system during winter, or cold weather,no problem of winter freezing of the water in the system is present. Asthe system operates through the use of the air within the buildingduring cold weather, the air-cooled condenser is not subject to the lowambient temperature of outside air during cold weather operation so thatthe compressor will operate at the desired head pressure and will nothave to operate at the reduced pressure caused by extreme cold aircondensation of the refrigerant passing through the condenser.

In addition to the foregoing of maintaining the refrigeration systemoperating within the optimum range, the heat of the refrigerant gases isused for the purpose of heating the air within the store so that thesaid air may at the same time maintain the refrigerating systemoperating under optimum conditions. Thus the air as heated performs thedual function.

Having fully described my invention, it is to be understood that I donot wish to be limited to the details herein set forth, but my inventionis of the full scope of the appended claims.

I claim:

1. In a refrigeration system of the type including, a compressor,operable for compressing a refrigerant which is a gas at normalatmospheric pressure, a condenser in which the gas is condensed to aliquid, means for conducting the refrigerant from the condenser to anevaporator in which the refrigerant is evaporated and heated, means forreturning the refrigerant to the compressor, the combination including aroom, a casing in which the condenser is positioned, a refrigeratedspace containing the evaporator positioned within said room, means inthe casing for drawing air over the condenser whereby said air isheated, the casing being provided with a first air inlet through whichair from the room may pass, a first outlet from the casing fordischarging the said heated air into the said room, a second inlet intothe casing for admitting air outside the room into the casing, and asecond outlet from the casing for discharging the outside air afterpassing over the condenser to the outside of the room, and means forselectively controlling the passage of air through said first and secondinlets and outlets.

2. In a refrigeration system, including a compressor for compressing arefrigerant gas, a condenser for condensing the compressed gas, anevaporator for evaporating the refrigerant condensed in the condenser toabsorb heat from a refrigerated space, a room containing saidrefrigerated space, means for passing air from. the room over thecondenser to extract heat therefrom, thereby to maintain a predeterminedoperating temperature range at said compressor, and simultaneously heatsaid air for discharge into said room at an elevated temperature therebyto heat said room, means associated with the condenser for admittingoutside air to pass over the condenser to extract additional heattherefrom, in the event the room temperature is too high to extractsufficient heat from said condenser to maintain the temperature at saidcompressor in said predetermined range, and means for discharging saidoutside air into the outside atmosphere when the temperature in saidroom exceeds a predetermined value.

3. In a refrigeration system, including a compressor for compressing arefrigerant gas, a condenser for condensing the compressed gas, anevaporator for evaporating the refrigerant condensed in the compressorto absorb heat from a refrigerated space, a room containing saidrefrigerated space, means for passing air from the room through thecondenser and back to the room thereby to heat the air and to maintainthe temperature of the air within the room at an elevated temperature,

the air heated by said condenser and returned to said room beingmaintained within said room at a temperature range tending to effectextraction of heat from said condenser in an amount which will maintaina desired head pressure of the refrigerant gas at the compressor, andmeans associated with the condenser for admitting outside air to passover the condenser and to be discharged into the outside atmosphere whenthe temperature within the room is higher than said temperature range.

4. In a refrigeration apparatus applicable for maintaining the operationof the refrigeration system under optimum conditions, said combinationincluding a compressor for compressing the normally gaseous refrigerant,an air-cooled condenser for condensing the compressed refrigerant to aliquid and an evaporator for the refrigerant, which combination includesa room in which the air temperature is to be maintained below apreselected maximum, a refrigerated space within but insulated from saidroom, the evaporator being within the refrigerated space, means forpassing air from said room over the condenser and discharging said airinto the room to heat the air within the room, and means operable, whenthe temperature of the air within the room reaches said maximum, fordrawing ambient air without the room to pass over the condenser and tobe discharged back exterior to the room and for arresting the flow ofair from within the room over the condenser and back to within the room.

5. In a refrigeration apparatus applicable for maintaining the operationof the refrigeration system under optimum conditions, said combinationincluding a compressor for compressing the normally gaseous refrigerant,an air-cooled condenser for condensing the compressed refrigerant to aliquid and an evaporator for the refrigerant, which combination includesa room, the temperature of which it is desired to be maintained below apredetermined maximum, a refrigerated space within but insulated fromsaid room, the evaporator being Within the refrigerated space, means forpassing air from the room over the condenser and discharging said airinto the room to heat the air within the room, means operable, when thetemperature of the air within the room reaches a maximum, for drawingambient air without the room to pass over the condenser and to bedischarged back exterior to the room and for arresting the flow of airfrom within the room over the condenser and back to within the room, andcooling means in the path of the ambient air for cooling the air to saiddesired maximum before said air passes over the condenser.

References Cited in the file of this patent UNITED STATES PATENTS1,942,295 Kerr Jan. 2, 1934 2,130,089 Hull Sept. 13, 1938 2,323,511Baker July 6, 1943 2,513,010 Deverall June 27, 1950 2,655,795 Dyer Oct.20, 1953 7,702,456 Ringquist Feb. 22, 1955

